Voting has begun in Venezuela's congressional elections, amid calls for a boycott by
opponents of President Hugo Chavez.

Five opposition groups are not taking part in the vote, saying the country's electoral council is biased in favor of the president.

The boycott makes it likely that pro-Chavez candidates will win two-thirds of the seats in the National Assembly. Analysts say with such a majority, pro-Chavez lawmakers could rewrite portions of the constitution, such as the clause that sets presidential term limits.

Mr. Chavez has said the boycott is a U.S.-backed "conspiracy" against his government. The U.S. State Department has repeatedly denied the accusations.

The Venezuelan government has deployed thousands of soldiers around the country to maintain order during the vote. Small explosions injured three people in the Caracas area on Friday.